This paper describes the relationship between the distribution of tuna and ENSO events in the Pacific Ocean which have occurred on a regular basis of 3-5 year terms. Annual catches and catch ratios of skipjack Funa, Katswonus pelamis and yellowfin tuna, Thunnus albacares largely increased during El $Ni~{n}o$ years, while it decreased during La $Ni~{n}a$ years. However, the effect of El $Ni~{n}o$ on the distribution of tuna seemed to be more significant to yellowfin tuna which usually occurr the upper thermocline depth increases due to the elevated thermocline in the Western and Central Pacific Ocean.